Dictionary Attack

Definition of Dictionary Attack

A dictionary attack is a type of cyber attack in which an individual or program attempts to gain unauthorized access to a system by systematically entering words from a predefined list, known as a dictionary. This attack method targets password-based authentication systems, trying multiple potential combinations to identify a correct one. Dictionary attacks are less time-consuming than brute force attacks but may be less effective if a user has a strong, unique password.


The phonetic pronunciation of the keyword “Dictionary Attack” would be:[dɪkʃəˌnɛri əˈtæk]

Key Takeaways

  1. A Dictionary Attack is a technique used by hackers where they try to systematically enter a large number of pre-compiled words or phrases as passwords, hoping to find the correct one to gain unauthorized access to a system or account.
  2. This type of attack can be effectively used against weak or common passwords, making it crucial for users to create strong, unique, and complex passwords to reduce the chances of a successful dictionary attack.
  3. To mitigate the risk of dictionary attacks, it is important to implement security measures such as enforcing password complexity requirements, enabling account lockout policies after a certain number of failed login attempts, and using multi-factor authentication.

Importance of Dictionary Attack

The technology term ‘Dictionary Attack’ is essential because it highlights a common cyber threat in which hackers attempt to gain unauthorized access to user accounts, systems, or sensitive information by systematically inputting various combinations of words or phrases from a pre-compiled dictionary.

This method specifically targets weak passwords, making it crucial for users and administrators to prioritize robust security practices, including developing strong, unique passwords and implementing multifactor authentication measures.

Awareness of dictionary attacks helps promote proactive approaches to cybersecurity and safeguard against potential breaches, safeguarding personal, corporate, and government data assets.


Dictionary attacks serve a strategic purpose in the world of cybersecurity, as they provide a means for hackers to crack passwords and gain unauthorized access to sensitive information. At its core, a dictionary attack is a technique used by cybercriminals to exploit weak passwords by systematically trying combinations of words from a pre-compiled list, or “dictionary.” This approach is highly effective when users rely on common words, phrases, or predictable sequences of characters for their passwords.

By using a large collection of potential passwords, including those that most people may consider to be strong, dictionary attacks can compromise an account relatively quickly compared to a brute force attack which trials every possible combination of characters. Dictionary attacks are often employed in a variety of cybercriminal endeavors, such as stealing sensitive data, accessing personal accounts, or breaching entire networks, all of which may have significant consequences for the target.

In order to counteract the threat posed by dictionary attacks, experts recommend using complex, unique passwords for each account and advise against the use of easily guessable words or phrases. Additionally, incorporating multi-factor authentication can help to strengthen account security even if a password has been compromised by a dictionary attack.

By understanding the purpose and usage of dictionary attacks, individuals and organizations can take preventative measures to protect themselves from the potential risks associated with this type of cyber breach.

Examples of Dictionary Attack

John’s email account gets hacked: In 2012, a hacker managed to gain access to John’s email account by using a dictionary attack. The attacker used an automated script that systematically tried common words and phrases in an attempt to crack John’s password. Since John had used an ordinary word as his password, the attacker was successful in gaining unauthorized access to his account and used it to send spam messages.

Ashley Madison data breach: In 2015, the Ashley Madison website, a dating platform for extramarital affairs, suffered a massive data breach. The attackers were able to obtain the user data, including hashed passwords. They used dictionary attacks to reverse-engineer these password hashes and exposed the weak passwords, causing embarrassment and potential relationship issues for millions of users.

Mat Honan iCloud hack: In 2012, Mat Honan, a senior writer at “Wired” magazine, found himself a victim of a dictionary attack when his iCloud account was compromised. The attacker was able to guess his weak password and took control of his account. Gaining access to his Apple ID, Gmail account, and Twitter profile, the hacker proceeded to wipe all of Honan’s data from his MacBook, iPhone, and iPad, and even hijacked his Twitter account to post malicious tweets. This incident highlighted the vulnerability of using weak, easily guessable passwords in the era of cloud computing.

FAQ: Dictionary Attack

What is a dictionary attack?

A dictionary attack is a type of cyber attack where an attacker systematically tries to login to a system using a precompiled list of words, phrases, or passwords, usually derived from dictionaries, in an attempt to gain unauthorized access.

How is a dictionary attack different from a brute force attack?

In a brute force attack, an attacker attempts all possible combinations of characters to find the correct password, whereas in a dictionary attack, the attacker relies on a list of commonly used words, phrases, or passwords to increase their chances of success.

What are the main risks of dictionary attacks?

The primary risk of a dictionary attack is the potential for unauthorized access to sensitive information, including email accounts, financial accounts, and other critical data. This may result in identity theft, financial loss, or compromises to an organization’s security.

How can I protect my accounts from dictionary attacks?

To protect your accounts from dictionary attacks, use strong, unique passwords that do not rely on common words or phrases. Include a combination of uppercase and lowercase letters, numbers, and special characters. Additionally, enable multi-factor authentication (MFA) whenever possible, and avoid using the same password for multiple accounts.

What measures can businesses take to prevent dictionary attacks?

Businesses can implement measures such as strong password policies, account lockouts after a specified number of failed login attempts, password encryption, CAPTCHAs to block automated bots, and regular security training for employees. Additionally, businesses should utilize security software and network monitoring tools to detect and respond to potential attacks.

Related Technology Terms

  • Brute Force Attack
  • Password Cracking
  • Hash Functions
  • Authentication Security
  • Key Space

Sources for More Information


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